Hey, I also have a HL-340 usb to serial adapter (shows up as CH-340 Com4) in windows xp Device Manger. Shows up OK and working properly in Device Manger but won't open up comport for use! I have about 5 different DRIVERS however everytime I uninstall the ORIGINAL driver - PROVIDER: wch.cn - DATE: 6.5.2006 - VERSION: 2.3.2006.6 and install a different one, this one keeps coming back!!! No matter what driver I install, when I go back to Device Manager to check it, this same one is in there??? I've made sure to uninstall it from everywhere, add/remove programs etc, so windows wouldn't reinstall automatically. I am running XP. Pulling my hair out are there any suggestions please? Thank you Jimbom

the driver has embedded its self in the system 32 files its going to be a pig to find now.

go in to add remove programs and remove the driver.
restart the pc.
then go in to my computer "c " drive , all programs folder.
look down the list for wch
if you find that folder delete it.
if you can't find that folder check inside anything that looks out of place to the programs you have installed on the pc.
look inside the folder before you delete it just to make sure you have found the correct one.

also check start , search , search for all files and folders , enter wch.cn ( with and without that . in its name )
see if windows can tell you where the files are

or you can use add remove programs to remove the driver, then use system restore built in to windows xp and restore the pc back to a date before you even installed the first driver.

Thanks Davey6 I used the restore function and it worked for getting rid of that driver. Problem now is when xp takes me to the installer and I choose "install from a list or specific location" click next. Remove the tick from " search removable media" and place it in " include this location in search" Click the browse icon that now alight, browse to folder you unpacked the into on your desktop. Double click that folder, now click ok, click next, windows will now start its search and look inside your folder for the correct driver for your device. When its finished restart your pc. NO WAY, no matter what I do now my computer, XP, will not let me search the hardrive or any of the removable media drives as even put the drives on a CD like stated by one of the guys here ( XP says they don't exist!). It grays out the OK button when I get to the folder on the desktop with the drive in it, and therefore won't let me finish the installation. The only one my computer will completely install is the Original driver which won't work! I've tried 4 other drivers besides the Original. I do check the device manager each time I try to install. I hate to put this on you, but please help me if you can. Thanks again, Jimbom

if its not installing from the disk or from a folder its not the correct driver.
I am sorry to say the best driver must be the one you got with the cable.

now you can install the driver again then call it up in device manager, right on the cbale and go down to properties and see if you can change the com port to com port 1 or 2 as that was standard settings for a old serial port.

now this has taken me ages to find but i think this is the update driver from wch that make the little switch over chip.
give this set of driver a wizz and see if they work.http://wch.cn/download/list.asp?id=73

Thanks again Davey6. I downloaded the updated version you gave me the link to and with the same results. When I right click on the problem in device manager, update driver, choose and install from a list, browse and when I click on the folder the driver is in the OK button goes gray and leaves me helpless as before! Incidently the driver has a file extension of .ddb ??? Thank you very for your time and effort. Jimbom

oh well was worth a shot, install your orignal driver again jimbom its clear xp thinks that is correct and see if you can change the comm port the way i listed above.
or look in control panel you may see the cable listed there as well once your driver is install you may be able to change the comm port it use's that way.

comm port 4 was used for modems back in the old days if you can change it to comm port one or two you stand a chance of connecting

ok i am going to add all three drivers that have worked for other members in to one post here as this is becoming a very long topic with drivers listed all the way through it.

Catsmaty's driver, can be found here.found here
to install that driver please follow catsmaty's advise.

catsmaty Wrote:
Hi,
Thank you, just emailed them to you on webmaster@davesdrivers.com, here is the step by step guide on how to use them:
I read allot about the problem with the Blue RS232 USB to Serial cable problems bought from fleebay, I bought one marked HL-340 and I followed the great post but none of the drivers worked for me till I got sick and I was about to through it in the bin till I found the solution, please follow these steps to solve your issues:

1- Download the winzip ebayhl-340 file on to your desktop and make sure that your cable is unplugged.
2- Make a new folder on your desktop
3- Unpack the winzip file in to your new folder
4- Burn a CD with the three folders found inside your new folder
5- Open the folder called HL-232-0108 and run the Setup For HugePine, if you get any messages press continue anyway.
6- Open the second folder called HL-232-340 and install the HL-340 and if you get any messages press continue anyway.
7- Open the folder called HL-232-2303 and then HL-2303, and run the HL-2303 setup, if you get a message saying to remove or reinstall, click on reinstall.
8- Reboot and then plug the cable, windows will recognize it as HugePine USB to serial and will ask you for the drivers, let windows install the driver automatically, again if you get any messages press continue anyway, once done it's ready to use.

you need to make sure everytime to use only the same USB port to avoid repeating these steps.

bobidiboo driver is the usb-serial zip on the bottom of this post

A driver i found for woodworker which is a different cable ch341ser/hl340 is the ch34rser zip at the bottom of this post.

if one of these drivers don't work for you please remember to uninstall it before you move on to the next or you will end up with a driver tossed salad in your system 32 folder then none of the drivers will work for you.

update 5/10/07
found another possible driver for another member today for the HL-340 cable.
this one is made by proflic and named PL-2303 I have added the driver to the board. pl2303.zip

My version of this 'imfamous' HL-340 device is USB\VID_4348&PID_5523 but thankfully Catsmaty's driver solution appears to have solved the problem I've been having with it. (..and to compound matters, I'm using Vista!!!!)
I can at last talk to and get response from my 'old' modem. Next step is to actually try and use it for fax etc. Maybe tomorrow:-)
Tks
TT

Hello everyone!!!
I'm new on this forum and in the begining want to say SORRY FOR MY ENGLISH!!! It's still not good :(. I'm from South Poland (central Europe). I found You because of HL-340 cable i have problem as You. Now i've got the driver- thanks to You- and i try to use it. We'll see if i can do this.

Many, many Thanks for this driver. I also tried all the other drivers I could find. I NEEDED it for my glucose meter.I am a diabetic and use the meter to down load blood readings to the computer to forward to the Dr. if necessary. Again :thankyou:

I am now going to lock this topic from any new post's if you have a problem with this cable please start a new thread.

many people are looking for these so please don't hard link to any of the drivers.
i will protect my site and any member looking for these drivers is need be by moving the whole lot to the locked out members section if hard linking continues.